4 new ways to solve the energy challengeJanuary 5, 2012: 5:00 AM ET
2. Harnessing the sun's power
Ever since cold fusion flopped spectacularly, the idea of finding an affordable way of replicating the sun's method of generating energy has become almost a joke. That may be about to change. Yes, the two major fusion reactor designs being explored in the research world -- one is called a tokamak and the other is inertial confinement systems -- show promise, but they are 20 to 30 years off. Also, they require either gigantic superconducting magnet systems or extra-fierce laser arrays and will cost tens of billions at best.
A small Canadian company called General Fusion has a new technology called magnetized target fusion, which could end up costing a fraction of what the other designs do. The privately funded project has attracted $32 million from investors including Amazon (AMZN) CEO Jeff Bezos. This is not the way things are traditionally done in Big Science, where only governments with deep pockets can afford to fund the R&D and construction of huge experimental machines. "If we had a 20-year project, we would never get the money. But we're promising to demonstrate a net energy gain in five years, and we're meeting our milestones," says CEO Doug Richmond. --S.F.B.
General Fusion's design shares aspects of the other two but aims to pull off fusion reactions using far simpler and cheaper hardware. The company's reactor draws on work begun more than 30 years ago at the U.S. Naval Research Lab. It uses 200 very powerful pneumatic pistons inserted through holes in a spherical metal vessel that Richardson compares to a "wiffle ball." Firing the pistons at precisely the right moment creates an acoustic shock wave that compresses hot liquid lead and lithium swirling around inside. Then, the injected deuterium-tritium gas encounters such heat and pressure that a fusion reaction briefly occurs. General Fusion brought the Navy's original idea to life by engineering control systems for the pistons that weren't possible a few decades ago.
If this long-shot technology works, it could provide clean, safe energy for generations to come.
Creating a fusion reaction
The easiest of all fusion reactions combines deuterium with tritium, which results in helium -- a safe, stable, environmentally friendly gas -- and a free neutron with a large energy output.